1. Field of the Invention
This invention relates to the field of aerosol spray cans. More specifically, the invention comprises a revised extension tube that locks to the spray cap when in use.
2. Description of the Related Art
Aerosol spray cans tend to deliver a diffused spray. In some applications, such as the precise deposition of lubricants, this diffused pattern is undesirable. Where precise application is needed, an extension tube has customarily been used.
FIG. 1 shows a prior art aerosol can 10. To dispense its contents, the user pressed down on spray cap 12. A diffused spray pattern then issues from orifice 16. Extension tube 18, which is simply a long hollow piece of plastic, can be inserted into orifice 16. In some prior art devices, orifice 16 is contained within nozzle insert 14. Gripping features, such as small ribs or pliable materials, can be included within nozzle insert 14. These help frictionally retain the portion of extension tube 18 that is thrust into orifice 16. However, those skilled in the art will know that this frictional retention approach is only marginally effective. The contents of aerosol can 10 issue forth under considerable pressure. They may also have significant lubricating value. These two factors degrade the prior art devices"" ability to retain extension tube 18 in position. In fact, it is not uncommon for an extension tube 18 to be launched out of spray cap 12 like a projectile.
The present invention comprises a modified spray cap and extension tube. Positive mechanical interlocking features are added which lock the extension tube to the cap. The extension tube therefore does not fly out of the cap when in use. The modified spray cap is configured so that a conventional diffused spray pattern is still achieved when the modified extension tube is removed.